[PATCH -next 2/2] Input: synaptics-rmi4 - Propagate correct number of rx and tx electrodes to F54

[Guenter Roeck <linux@roeck-us.net>]

F54 diagnostics report functions provide data based on the number of
enabled rx and tx electrodes, which is not identical to the number of
electrodes reported with F54:Query0 and F54:Query1. Those values report
the number of supported electrodes, not the number of enabled electrodes.
The number of enabled electrodes can be determined by analyzing F55:Ctrl1
(sensor receiver assignment) and F55:Ctrl2 (sensor transmitter assignment).

Propagate the number of enabled electrodes from F55 to F54 to avoid
corrupted output if not all electrodes are enabled.

Fixes: 3bbacb89704fi ("[media] Input: synaptics-rmi4 - add support for F54 ...")
Cc: Nick Dyer <nick@shmanahar.org>
Cc: Andrew Duggan <aduggan@synaptics.com>
Cc: Chris Healy <cphealy@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
Notes:
- The Fixes: SHA might not be accurate if the originating branch is rebased.
- This patch depends on the preceding patch (which, strictly speaking, does
  not fix anything).

 drivers/input/rmi4/Kconfig   |  1 +
 drivers/input/rmi4/rmi_f54.c | 14 ++++++++++----
 drivers/input/rmi4/rmi_f55.c |  7 +++++++
 include/linux/rmi.h          |  3 +++
 4 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/drivers/input/rmi4/Kconfig b/drivers/input/rmi4/Kconfig
index 11ede43c9936..d7129928cde6 100644
--- a/drivers/input/rmi4/Kconfig
+++ b/drivers/input/rmi4/Kconfig
@@ -67,6 +67,7 @@ config RMI4_F54
 	depends on RMI4_CORE
 	depends on VIDEO_V4L2=y || (RMI4_CORE=m && VIDEO_V4L2=m)
 	select VIDEOBUF2_VMALLOC
+	select RMI4_F55
 	help
 	  Say Y here if you want to add support for RMI4 function 54
 
diff --git a/drivers/input/rmi4/rmi_f54.c b/drivers/input/rmi4/rmi_f54.c
index cf805b960866..9cb3aa733f0f 100644
--- a/drivers/input/rmi4/rmi_f54.c
+++ b/drivers/input/rmi4/rmi_f54.c
@@ -216,8 +216,10 @@ static int rmi_f54_request_report(struct rmi_function *fn, u8 report_type)
 
 static size_t rmi_f54_get_report_size(struct f54_data *f54)
 {
-	u8 rx = f54->num_rx_electrodes ? : f54->num_rx_electrodes;
-	u8 tx = f54->num_tx_electrodes ? : f54->num_tx_electrodes;
+	struct rmi_device *rmi_dev = f54->fn->rmi_dev;
+	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
+	u8 rx = drv_data->num_rx_electrodes ? : f54->num_rx_electrodes;
+	u8 tx = drv_data->num_tx_electrodes ? : f54->num_tx_electrodes;
 	size_t size;
 
 	switch (rmi_f54_get_reptype(f54, f54->input)) {
@@ -401,6 +403,10 @@ static int rmi_f54_vidioc_enum_input(struct file *file, void *priv,
 
 static int rmi_f54_set_input(struct f54_data *f54, unsigned int i)
 {
+	struct rmi_device *rmi_dev = f54->fn->rmi_dev;
+	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
+	u8 rx = drv_data->num_rx_electrodes ? : f54->num_rx_electrodes;
+	u8 tx = drv_data->num_tx_electrodes ? : f54->num_tx_electrodes;
 	struct v4l2_pix_format *f = &f54->format;
 	enum rmi_f54_report_type reptype;
 	int ret;
@@ -415,8 +421,8 @@ static int rmi_f54_set_input(struct f54_data *f54, unsigned int i)
 
 	f54->input = i;
 
-	f->width = f54->num_rx_electrodes;
-	f->height = f54->num_tx_electrodes;
+	f->width = rx;
+	f->height = tx;
 	f->field = V4L2_FIELD_NONE;
 	f->colorspace = V4L2_COLORSPACE_RAW;
 	f->bytesperline = f->width * sizeof(u16);
diff --git a/drivers/input/rmi4/rmi_f55.c b/drivers/input/rmi4/rmi_f55.c
index 268fa904205a..b95a5d60ba96 100644
--- a/drivers/input/rmi4/rmi_f55.c
+++ b/drivers/input/rmi4/rmi_f55.c
@@ -41,6 +41,8 @@ struct f55_data {
 
 static int rmi_f55_detect(struct rmi_function *fn)
 {
+	struct rmi_device *rmi_dev = fn->rmi_dev;
+	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
 	struct f55_data *f55;
 	int error;
 
@@ -60,6 +62,9 @@ static int rmi_f55_detect(struct rmi_function *fn)
 	f55->cfg_num_rx_electrodes = f55->num_rx_electrodes;
 	f55->cfg_num_tx_electrodes = f55->num_rx_electrodes;
 
+	drv_data->num_rx_electrodes = f55->cfg_num_rx_electrodes;
+	drv_data->num_tx_electrodes = f55->cfg_num_rx_electrodes;
+
 	if (f55->qry[F55_PHYS_CHAR_OFFSET] & F55_CAP_SENSOR_ASSIGN) {
 		int i, total;
 		u8 buf[256];
@@ -81,6 +86,7 @@ static int rmi_f55_detect(struct rmi_function *fn)
 					total++;
 			}
 			f55->cfg_num_rx_electrodes = total;
+			drv_data->num_rx_electrodes = total;
 		}
 
 		error = rmi_read_block(fn->rmi_dev,
@@ -93,6 +99,7 @@ static int rmi_f55_detect(struct rmi_function *fn)
 					total++;
 			}
 			f55->cfg_num_tx_electrodes = total;
+			drv_data->num_tx_electrodes = total;
 		}
 	}
 
diff --git a/include/linux/rmi.h b/include/linux/rmi.h
index e0aca1476001..45734f1343b3 100644
--- a/include/linux/rmi.h
+++ b/include/linux/rmi.h
@@ -345,6 +345,9 @@ struct rmi_driver_data {
 	u8 pdt_props;
 	u8 bsr;
 
+	u8 num_rx_electrodes;
+	u8 num_tx_electrodes;
+
 	bool enabled;
 
 	void *data;
-- 
2.5.0